Ben Bernanke has perfected his version of the dollar dance — lots of flourishes and a little footwork.

The Federal Reserve chief yesterday straddled the economic fence as he acknowledged the greenback’s troubling slide, but suggested he won’t be stepping in to stop it anytime soon.

In a speech to the Economic Club of New York, Bernanke’s soothing words worked — for a while. The buck lifted a bit before sliding to 15-month lows.

“Bernanke is trying to use words — not interest rates — to prevent the dollar from going even lower,” said Jay Bryson, global economist at Wells Fargo Securities.

Here’s the bad news: The euro is now worth $1.50, and the pound, $1.70.

Central banks are worried their own currencies are getting too high in relation to the sinking dollar, making their exports and internal financing costs rise. Instead, analysts say Bernanke intends to keep interest rates — in effect the cost of dollars — at historic lows to keep the greenback devalued for now.

At the same time, however, Bernanke said he would monitor the slide to keep it out of a perceived danger zone.

“We are attentive to the implications of changes in the value of the dollar,” Bernanke said, adding he would “monitor these developments closely.”

His comments come as economists worry that keeping US rates too low could form a currency bubble. “It’s extraordinarily difficult to tell” if a bubble is forming, Bernanke acknowledged. “It’s not obvious to me in any case.”

If a bubble did form, however, “we [will] use our interest rate tools to try to meet our mandate: full employment and price stability.”